Electromagnetic relay

ABSTRACT

Electromagnetic relay having a relatively thin insulating member as the base for the relay which forms a mounting for the electromagnet, armature and relay contacts. The contacts for the relay comprise a series of sets of contact springs. Each set of contact springs is spaced along the base and arranged on opposite sides of an acutator member for the contacts and made from insulating material. The contact springs are assembled in the insulating member by merely sliding the springs into position in the base with all of the contacts arranged in a common plane, to provide a relay which may be readily assembled and is of minimum height and has all of the parts of the relay mounted on the base and readily accessible.

United States Patent [191 Aidn et a1.

ELECTROMAGNETIC RELAY [75] Inventors: Martin Aidn; Alois Ruhland, both of Muenchen, Germany [73] Assignee: Siemens AG., Berlin & Munich,

Germany [22] Filed: Apr. 12, 1973 [21] Appl. No.: 351,103

[30] Foreign Application Priority Data 1 Apr. 17. 1972 Germany 2218494 [52] US. Cl. 335/202, 335/133 [51] Int. Cl. H0lh 13/04 [58] Field of Search 335/131, 129, 133, 132, 335/202 [56] References Cited UNITED STATES PATENTS 3 2,259,183 10/1941 Snavely 335/131 2,755,356 7/1956 Jucker 335/129 2,886,668 5/1959 Steward et al. 335/133 2,951,922 9/1960 Myrent et a1. 335/133 1 July 16, 1974 3,042,774 7/1962 Hawkins 335/133 3,509,502 4/1970 Maynard et a1 335/202 Primary Examiner-Harold Broome Attorney, Agent, or Firm-Hill, Gross, Simpson, Van Santen, Steadman, Chiara & Simpson ABSTRACT Electromagnetic relay having a relatively thin insulating member as the base for the relay which forms a mounting for the electromagnet, armature and relay contactsnThe contacts for the relay comprise a series of sets of contact springs. Each set of contact springs is spaced along the base and arranged on opposite sides of an acutator member for, the contacts and 10 Claims, 7 DrawingvFigures ELECTROMAGNETIC RELAY FIELD OF THE INVENTION Electromagnetic relay having a base of insulating material and forming a common attachment means for the contact means and magnetic system of the relay.

BACKGROUND, SUMMARY AND ADVANTAGES OF THE INVENTION The use of a single insulating member as the base for a relay and unitary mounting for contact springs and the magnetic system therefor, which can be attached to or plugged into a conductor plate, offers many advantages over most common relays utilizing separately assembled contact spring sets, which are only united to the magnet system after assembly of the system, in that it reduces assembly time and labor, uses fewer individual parts and enables the manufacturing tolerances between the magnet system and individual contact springs to be maintained, due to the location of all parts of the relay in a prescribed place in the base, forming a basic insulating member for the relay.

Such a relay with a single plastic insulating member as an attachment member is described in the German Auslegeschrift No. 1,805,583. The relay construction of this patent, however, is a relatively high narrow structure and cannot be used for certain fields of application, as for example, for use on conductor plates. In addition, the assembly of the relay is relatively complicated and time-consuming since the contact springs have to be attached on both sides of the base for the relay and also have to be inserted first in a cross direction and then in a longitudinal direction.

Relays with E-shaped magnet systems are common for use on conductor plates. In these relays, contact springs have to be moved vertically to the plane of the conductor plate. The functional parts of the relay are, therefore, necessarily arranged in a cumbersome and difficult to assemble manner, one being exposed above the other because of the low admissible construction height for such relays. With such relays, it is extremely difficult, if not impossible, to replace an individual part or even exchange an individual part for another part of a different type without changing all of the parts. Moreover, because of the lower height requirements for such relays, they can only be provided with a limited number of contact springs. Such a relay, among others, is shown and described in the German Auslegeschrift No. 1,948,725. Another design of a flat relay is shown in the German Offenlegungsschrift No. 2,016,903. In this patent, a relay with a hinged armature system has two nested contact spring sets, which are displaced with respect to each other and operated together. These contact spring sets, however, are in layers makingit impossible to exchange individual contact springs. Furthermore, construction height cannot be kept as low as desired because of the nested arrangement of the contact springs and the required security distance between the contact springs. This relay, therefore, has all of the disadvantages of the contact springs arranged in layers and particularly the disadvantage of making it extremely difficult to-maintain the required tolerance between the springs.

The present invention provides a relay with a common base made from insulating material, forming a base both for the contact springs and magnet system and arranged for use on conductor plates and having a very low height and a simple assembly, providing good functional control and ready exchange of individual parts. This is attained by designing the insulating base for the relay as a flat relatively thin member having a bottom side serving as a soldering side and having all functional elements of the relay arranged one after the other to accommodate ready inspection and repair of the relay.

This relay construction has the advantage that the assembly can be carried out in a simple and expeditious manner either by hand or machine. The particular arrangement of contact spring operating member and magnet system on one level along the insulating base enables the contact members to be inserted in the base independently of each other and to be readily adjusted or exchanged. The attachment of the individual contact parts may be in the form of ribs projecting upwardly from opposite sides of the insulating base and extending parallel to the direction of movement of the contact springs. I

Preferably the contact springs are attached between two'opposite ribs of the insulating member as by gluing, pressing, etc. The simplest way is by anchoring the contact springs by integral contact flaps, which may extend at right angles to the contact springs. All electrical connections to the contact springs and the relay coil.

are passed through windows extending through the base in the bottom or solder side of the base. In a preferred embodiment of the invention, the contact springs are generally L-shaped with the short leg of the L forming a soldering leg and the long leg of the L forming a contact leg, movable in a direction parallel to the basic plane of the base.

In the preferred embodiment of the invention illustrated, all contact springs are inserted individually in slots formed in attachment ribs of the base. The contact springs may, however, be inserted as a prefabricated block, as for example, molded into the insulating base of the relay, and anchored between the attachment ribs. In the preferred embodiment of the invention, the contact springs may be arranged in two rows with their free ends facing each other. All contact springs of the relay may be operated by a common shifter arranged between the two rows of contact springs, which may serve as an intermediate insulating wall between the facing ends of the contact springs and thereby enable the distances between the rows of contact springs to be maintained at a minimum distance.

A further advantage of the present invention is the arrangement of the magnet system for the relay in such a way that it is anchored to extend parallel to the basic plane of the insulating base and movement of the armature is parallel to this plane. This is attained by rib or support wall serving as an attachment wall for the magnet system and extending inwardly from the attachment ribs for the contact springs. The magnet system can be assembled and located in an exact position at one end of the base to extend transversely thereof prior to the assembly of the contact springs. The magnet assembly being accurately assembled in position, it is unnecessary to later adjust the position of the magnet assembly after assembly of the contact springs to the base. The magnet assembly may be attached by means of a screw extending through a yoke for the electromagnet and a lug or rib extending inwardly of the attachment lugs for the contact springs.

without departing from the spirit and scope of the novel concepts of the disclosure.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial horizontal sectional view taken through a relay constructed in accordance with the principles of the present invention looking at the relay assembly in plan.

FIG. 2 is a transverse sectional view taken substantially along line A-B of FIG. 1'.

FIG. 3 is a modified form of contact arrangement and operating means therefor from that shown in FIGS. 1 and 2.

FIG. 4 is a partial fragmentary sectional view taken through the attachment means for the yoke and magnet coil to the base.

FIG. 5 is a sectional view taken substantially along line C-D of FIG. 4.

FIG. 6 is an exploded view illustrating the return spring, the contact actuator and a portion of the armature moving the actuator against the return spring; and

FIG. 7 is a partial fragmentary view with parts in section illustrating a different connection of the actuator to the return spring from that shown in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF INVENTION FIGS. 1 and 2 illustrate the basic structure of the relay of the present invention. The relay includes a base 1 made from a suitable insulating material and designed as a flat thin part. The base has marginal side and end walls 1a and lb respectively. The side and end walls may be shouldered to receive a cover 20 which with said base and side and end walls, forms a housing for the relay. An electromagnetic system for the relay is shown as including a yoke 2 supporting an electromagnetic coil 5 and shown in FIG. 1 as being secured to a lug 4 extending inwardly of an end wall lb. In addition to the yoke 2 and the electromagnetic coil 5, the magnetic system includes a core 50, and disks 6 and 6a for the electromagnet and an electrically energizable winding 7 wound about the core 50 between said end disks. The electromagnetic system also includes an armature 8 of an angular form rockable about the free end of the yoke 2 to actuate an actuator 16 against a return spring 17, seated in the opposite wall of the base from the electromagnet 5 and returning said actuator and armature into the position shown in FIG. 1, upon deenergization of the electromagnet. A support plate 9 is supported on the lug 4 under the head of the screw 3 to limit the tightening of the screw on the lug 4 and yoke 2. The support plate 9 has a connecting lug 10 formed as a part thereof and extending through the bottom of the base 1, to serve as a ground connection (FIG. 4). The positive energizing terminal for the electromagnetic coil may also extend through the bottom of the base and is of a well-known form so need not herein be 4 1 shown or described in detail. Contact springs l2, l3 and 14 are symmetrically arranged alongthe base 1 in two rows and extend toward each other from attachment ribs projecting upwardly from the top of said base and inwardly of the side walls 1b. The individual contact springs have right-angled contact legs 12a forming solder legs and have a resilient contact leg 12b. The contact springs 12, 13 and 14 extend along slots 15a formed in the ribs 15 and may be glued or otherwise secured thereto. As shown in FIG. 1, thecontact springs 14 are resting contact springs biased to make contact with the middle contact springs l3'and biasing said middle contact springs into contact engagement with the contact springs 12.

The contact springs may be made of one piece 0 may be composed of two parts. As for example, the solder leg 12a for contact springs 12 may be of a larger thickness than the spring leg 12b, which may be welded or otherwise secured thereto. Moreover, in some instances it may be desirable to individually anchor all of the contact springs in the insulating material in the slots 15a. In the embodiment of the invention shown, the

contact springs are inserted in the slots 15a and are glued or otherwise secured to the insulating material, although they may be fused in the insulating material, if desired. The actuator or shifter 16 serves asa divider between the sets of contacts on opposite sides thereof and has three sets of oppositely extending lugs 16a each of which oppositely extending aligned lugs extend between the contact springs 12 and 14. The actuator has a reduced diameter end portion 27 extendingupwardly from the center thereof through anapertured portion 28 of the return spring 17. The return spring 17 is shown as being a bowed spring abutting the inside of the wall 1a of the base 1'. The opposite end of the actuator is shown as having lugs 25'depending from opposite sides thereof and extending within slots 26 formed in the inwardly extending leg of the armature 8. Upon energization of the magnet coil 5 of the electromagnet, the armature 8 will rock about the end of the yoke 2 and move the actuator 16 against the spring 17. The actuator lugs 16a will engage under the contact springs 14 and move said contact springs 14 out of engagement with the contact springs 13. The contact springs 12 will thus engage the contact springs 13 by their own bias to make an electrical connection between the contacts 12 and 13.

The contacts as shown in FIG. 1, are thus indirectly operated self-pressure contacts and in the case of a non-excited magnet system, the resting contact springs 14 contact the middle contacts 13 by their own bias while the working contacts 12 are lifted from the middle contacts 13 by the lugs 16a of the actuator 16 by the stored up energy of the return spring 17.

It should here be noted that the rib 15 adjacent the armature 8 is so formed as to extendclosely adjacent the armature 8 and serve as a retainer for said armature and to prevent said armature from shifting out of place tion of the magnet coil is moved by a lug 16a to engage a working contact 23.

In FIGS. 4 and 5, detail sectional views are shown illustrating the mounting of the magnet yoke 2 on the lug 4 by a screw 3. Tightening of the screw brings the entire magnetic system, including the yoke, the electromagnetic coil and armature in fixed relation with respect to the contact springs and also secures the connecting lug to project from the base 1 and form a terminal for grounding the magnet coil. In the hollow space between the yoke 2 and the screw 3, a glue or resin drop 24 is inserted to provide a gluing as well as bolting connection for the yoke and magnet coil.

The exploded view of FIG. 6 shows the connection between the armature 8, the shifter 16 and the return spring 17. Said shifter 16 has depending lugs 25 fitting into slots 26 of the armature 8. The opposite end of said shifter 16 has a reduced diameter end portion in the form of a peg 27 projecting upwardly therefrom into the apertured portion 28 of the return spring 17. This connection materially reduces friction during operation of the shifter.

In FIG. 7 we have shown an actuator 16 like that shown in FIG. 6, except in place of the peg 27, the actuator has a semispherical headed end 29 fitting within a socket formed in the return spring 17 as by a pressing operation. This form of connection reduces friction and wear between the actuator and return spring.

We claim as our invention:

1. In a flat compact electromagnetic relay particularly adapted for circuit boards,

an insulating member having a flat base,

parallel side and end walls extending perpendicular to said base,

a magnetic coil between said side walls at one end of said base and having an axis extending parallel to a plane top surface of said base,

a yoke detachably supported on a side wall of said base and supporting said magnet coil to extend along one end of said base,

a plurality of sets of contact springs spaced from said magnet coil along said base and extending from opposite side walls of said base toward the center of said base for movement in parallel relation with respect to the top plane surface of said base,

an armature rockingly mounted on said yoke and extendingalong one end of said magnet coil,

an actuator engaging said armature and movable in the plane of said base for moving said contact springs in certain predetermined positions,

a single flat return spring at the opposite end of said base from said magnet coil and having operative connection with said actuator for returning said actuator and moving said contacts into certain other positions,

the bottom surface of said base forming a connector side for said coil and for said contact springs and the side walls of said base forming insulated surfaces, the contact springs, actuator, armature, return spring and magnet coil being arranged adjacent each other with the operative parts parallel with the plane of the top surface of said base and movable in said plane.

2. The electromagnetic relay of claim 1, wherein opposite side walls of said base have ribs extending inwardly therefrom having parallel slots therein forming attachment members for said contact springs, wherein windows lead from said slots through said base and electrical terminals extend from said contact springs through said slots to the solder side of the relay, and wherein a lug extends inwardly of one of said ribs and forms an attachment member for said yoke.

3. The electromagnetic relay of claim 2, in which the contact springs are L-shaped in plan and have a short leg extending through a slot and window and forming a terminal leg and a long leg forming a contact leg.

4. The electromagnetic relay of claim 3, in which the contact legs consist of a thin spring material and the solder legs are of a thicker material and have the contact legs welded thereto.

5. The electromagnetic relay of claim 4, in which the contact springs are fixed in said slots at their outer ends and extend parallel with each other andterminate at their inner ends in spaced relation with respect to each other.

6. The electromagnetic relay of claim 5, in which the contact springs are each in sets of three and comprise mobile contact springs facing each other and the actuator is arranged between said rows of contact springs and is made from an insulating material for shifting'certain of said contact springs in one direction upon energization of said electromagnetic coil and in an opposite direction upon deenergization of said coil by the action of said return spring.

7. The electromagnetic relay of claim 6, including an angled armature having one leg extending along an end of said electromagnetic coil, a second leg at an angle to said one leg and extending along said yoke and having a fulcrum point on the end of said yoke effecting movement of said armature parallel to the basic plane of said base.

8. The electromagnetic relay of claim 7, in which the juncture of the legs of said armature rockable about said yoke on the inner sides thereof is relatively close to an associated rib on the outer side thereof retaining said armature in position on said yoke upon jarring of said relay.

9. The relay of claim 8, in which the lug extends inwardly of the rib, opposite the point of rocking movement of the armature, the yoke extends along the bottom of said lug, a contact extends along said lug through the bottom of said base and a screw secures said contact to one side of said lug and said yoke to the opposite side of said lug with said contact extending through said base and forming a ground terminal for said electromagnetic coil.

10. The electromagnetic relay according to claim 9, in which the side and end walls of said base have an outwardly opening recess extending about said side and end walls and in which a cover fits along said recess and forms a closure for said base and the electromagnetic contact system. 

1. In a flat compact electromagnetic relay particularly adapted for circuit boards, an insulating member having a flat base, parallel side and end walls extending perpendicular to said base, a magnetic coil between said side walls at one end of said base and having an axis extending parallel to a plane top surface of said base, a yoke detachably supported on a side wall of said base and supporting said magnet coil to extend along one end of said base, a plurality of sets of contact springs spaced from said magnet coil along said base and extending from opposite side walls of said base toward the center of said base for movement in parallel relation with respect to the top plane surface of said base, an armature rockingly mounted on said yoke and extending along one end of said magnet coil, an actuator engaging said armature and movable in the plane of said base for moving said contact springs in certain predetermined positions, a single flat return spring at the opposite end of said base from said magnet coil and having operative connection with said actuator for returning said actuator and moving said contacts into certain other positions, the bottom surface of said base forming a connector side for said coil and for said contact springs and the side walls of said base forming insulated surfaces, the contact springs, actuator, armature, return spring and magnet coil being arranged adjacent each other with the operative parts parallel with the plane of the top surface of said base and movable in said plane.
 2. The electromagnetic relay of claim 1, wherein opposite side walls of said base have ribs extending inwardly therefrom having parallel slots therein forming attachment members for said contact springs, wherein windows lead from said slots through said base and electrical terminals extend from said contact springs through said slots to the solder side of the relay, and wherein a lug extends inwardly of one of said ribs and forms an attachment member for said yoke.
 3. The electromagnetic relay of claim 2, in which the contact springs are L-shaped in plan and have a short leg extending through a slot and window and forming a terminal leg and a long leg forming a contact leg.
 4. The electromagnetic relay of claim 3, in which the contact legs consist of a thin spring material and the solder legs are of a thicker material and have the contact legs welded thereto.
 5. The electromagnetic relay of claim 4, in which the contact springs are fixed in said slots at their outer ends and extend parallel with each other and terminate at their inner ends in spaced relation with respect to each other.
 6. The electromagnetic relay of claim 5, in which the contact springs are each in sets of three and comprise mobile contact springs facing each other and the actuator is arranged between said rows of contact springs and is made from an insulating material for shifting certain of said contact springs in one direction upon energization of said electromagnetic coil and in an opposite direction upon deenergization of said coil by the action of said return spring.
 7. The electromagnetic relay of claim 6, including an angled armature having one leg extending along an end of said electromagnetic coil, a second leg at an angle to said one leg and extending along said yoke and having a fulcrum point on the end of said yoke effecting movement of said armature parallel to the basic plane of said base.
 8. The electromagnetic relay of claim 7, in which the juncture of tHe legs of said armature rockable about said yoke on the inner sides thereof is relatively close to an associated rib on the outer side thereof retaining said armature in position on said yoke upon jarring of said relay.
 9. The relay of claim 8, in which the lug extends inwardly of the rib, opposite the point of rocking movement of the armature, the yoke extends along the bottom of said lug, a contact extends along said lug through the bottom of said base and a screw secures said contact to one side of said lug and said yoke to the opposite side of said lug with said contact extending through said base and forming a ground terminal for said electromagnetic coil.
 10. The electromagnetic relay according to claim 9, in which the side and end walls of said base have an outwardly opening recess extending about said side and end walls and in which a cover fits along said recess and forms a closure for said base and the electromagnetic contact system. 